The Institute of Medicine (IOM) report identified significant research gaps in the field linked to a critical shortage of child and adolescent psychiatric physician investigators. The National Institute on Drug Abuse (NIDA) has responded to this call by establishing a strong linkage with the American Academy of Child and Adolescent Psychiatry (AACAP) that resulted in the successful training of 6 child/adolescent psychiatrists as career addiction research investigators under the first "AACAP Physician Scientist Program in Substance Abuse" (K12). The primary aim of this competing renewal application is to build on the success of the previous award by proposing to train six more career investigators by: 1) Identifying and recruiting the most highly qualified candidates with the greatest potential as independent investigators; 2) to significantly expand the collaborative network of addiction research mentors and training centers to support the career development of junior faculty trainees, by utilizing NIDA's Clinical Trials Network (CTN) as a training platform; and 3) to expand the number of institutions with clinical addiction research and programs. Special emphasis will be placed on the recruitment of minority candidates and candidates from home institutions with limited research and training opportunities. A supervisory committee of distinguished senior investigators in child and adolescent psychiatry and addiction research will work with trainees to design, implement and monitor individualized research training programs to assure the successful career development of the junior investigators under this award.